1. Field of the Invention
Embodiments of the present invention relate to the field of semiconductor devices. More specifically, embodiments of the present invention relate to the measurement of leakage current in a semiconductor device.
2. Related Art
One of the challenges facing the users and designers of integrated circuits is managing the power produced by a chip. The power dissipated by a digital chip has two basic sources: switching current, and leakage current. When a gate is switching from one logical value to another, there is a brief period of time when current passes through the transistors dissipating power in the form of heat. Historically, this switching current has been the focus of attention because it was substantially greater than the nominal leakage current that occurred when the gate was not switching and the transistors were “off.”
However, with smaller geometries and reduced operating voltages, the leakage current is a significantly larger proportion of the power production problem. Thus, chip designers need to develop both on-chip and off-chip techniques for dealing with leakage current. One challenge faced by designers is accurately measuring the amount of leakage current that is actually present on a particular chip.
Back gate biasing (“backbias”) is commonly used to control the leakage current, and another challenge here is measuring the amount of leakage current under various backbias conditions.